bolt not locking back on last shot

[sneaky one]

terry, triple check all the parts. I had a lower sent back to me from cav. arms-in 08' w/ a 9mm spring & buffer inside---I sent it empty. What fun that was to figure out.

H2-& a stock spring works well for most here-some use h3 & ??? spring. Keep it simple, that way you can always find a part -where ever you may roam.
Could it be--under loaded fact. ammo? That's what I see as a load is worked upward, that and the gas issue=too little to lock it back.

[terrywick4]

Not sure what it is, tried a new buffer spring and standard buffer
(been using H2) today and didn't help. Don't think it is a gas issue, I've run the gas block full open. I've hooked a air line to the gas tube and seems to have plenty when I blow thru it, more so than the 223. gonna have to wait till it warms up now, another snow storm is here and I'm hobbling around on a fractured leg.

[Shivesy]

In my opinion you accomplished nothing by adding a adjustable gas block and running it wide open. Would that not be the same as just a basic gas block? Adjustable gas block wide open and a basic gas block is going to flow the same amount of gas, whatever the gas port will allow. How far are your spent cartridges landing? I would quess 3'-4' would be common. Are they flying that far? I understand using a adjustable gas block if your over gassed because then you can tone down you gas flow. Some folks I have talked to open up their gas port a little larger than needed then tone it down as needed via an adjustable gas block. I don't really agree with that method but that is a different way to monitor gas flow.
As far as the dented cases. I was under the impression that it was a common issue. I run the soft piece of velcro on the deflector and now no more dented cases. Do you know your gas port size? Just a thought but you might want to open up your port hole just a tad more and if that don't do it then tone your gas back down with the adj. block. I also helped a friend with a situation like yours that was not gas related. The vendor sold him a longer buffer spring than what he needed. He had a collapsable stock and they sold him a fixed butt stock spring. We cut the spring down as a quick fix and his rifle cycled properly. Good luck and I hope you get it figured out.

[babaganoush]

As far as the dented cases. I was under the impression that it was a common issue. I run the soft piece of velcro on the deflector and now no more dented cases.

+1 on the gas block running WFO being counter productive.

I also had an issue with dented cases, and read about the velcro trick. Instead, I opted to shorten the ejector spring by 1.5 coils with a Dremel tool. It tamed that problem quite effectively. Brass now lands at my 4 o'clock at about 4 feet, with no dents and no brass transfer on the deflector.

[rushmc]

I had an issue with a lower and catch combination. (Brands dont matter at this point) What I had happening was the lower and catch lined up in such a way that the catch was hitting on the lower so it would not engage far enough to catch the bolt. I removed the catch, (I could see where it was hitting at that time, I found it by comparing how far it moved to a rifle that worked) filed off a bit of metal and it has worked ever since